<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>

</body>
<script>
    // * `instanceof`是如何判断的?
    // * 表达式: A` instanceof` B
    // * 如果B函数的显式原型对象在A对象的原型链上, 返回true, 否则返回false
    {
        const Box = function(){

        }
        const obj = new Box();
        console.log(obj instanceof Box);// true
        console.log(obj instanceof Object);// true
        // console.log(obj instanceof null);// 报错
        console.log(obj.__proto__.__proto__.__proto__ === null)
    }
</script>
</html>